Copper phtalocyanine pigments are extremely light stable pigments, which range in color from vivid blues to greens. In addition, these pigments exhibit very high chemical and heat stabilities. Because of their stabilities and their attractive, natural looking colors, they are being used extensively as a colorant in a variety of plastic articles of manufacture intended for outdoor use, for instance, in outdoor carpeting and in synthetic turfs. In these applications, the plastic resin is usually a polyolefin resin, especially a polypropylene based resin.
Usually the outdoor carpetings and turfs are permanently installed for the purpose of simulating grass in locations where natural growth is impractical due to wear, or climatic conditions, e.g. excessive heat and sunlight, or a combination thereof. In order to prevent degradation of the polymer resins to heat, exposure to air and sunlight, various stabilizers such as antioxidants and UV stabilizers are incorporated into said resins. Although the average useful life of the pigmented resin is improved by the incorporation of the abovementioned stabilizers, a further improvement would be most desirable.
It is therefore a main object of the present invention to provide a polyolefin resin pigmented with copper phtalocyanine pigments having an improved stability against deterioration due to heat and oxygen.
Other objects will become apparent from the detailed description and appended claims.